This invention relates to a stable, novel formulation of the bitter-tasting deglycyrrhizinated licorice (DGL) which can be formulated to contain other ingredients known as pharmaceutical excipients that will enhance the dissolution and disintegration of the active ingredient, DGL, thereby making it unnecessary to chew tablets containing the DGL. These improved formulations can be swallowed and rapid and complete disintegration in the gastrointestinal tract can be achieved in order to release the ulcer-healing ingredient, DGL.
Licorice has been used for many years in the treatment of gastric disorders. In recent times the serious side effects of licorice became a major drawback to its use and in 1950 it was discovered that the constituent causing the major disturbance was glycyrrhizinic acid.
In the early 1950's it was decided to try and remove this ingredient and in 1952 a report appeared in Munchen Medizinische Wochenschrift by Dr. Irte that tablets of Caved-S were being used in treatment of peptic ulcers. This preparation (Caved-S) contained Bismuth Subnitrate (now known to be neurotoxic) and three other ingredients were used as flavoring or aromatic agents, Rhamni frangula cortex, Calami rhizoma and Foeniculi fructus. These latter two agents are described as being aromatic and irritants to the bowel. The DGL was prepared by a method which was described in Zagt U.S. Pat. No. 3,046,195.
Caved-S has the formulation:
______________________________________ (1) Succ licorice deglycyrrhizinate (DGL) 0.38 gram (2) Bismuth subnitrate 0.10 gram (3) Aluminum hydroxide 0.10 gram (4) Magnesium subcarbonate 0.20 gram (5) Sodium bicarbonate 0.10 gram (6) Calami rhizoma 0.01 gram (7) Rhamni frangula cortex 0.03 gram (8) Foeniculi fructus 0.02 gram (9) Excipients q.s. ad. ______________________________________
This mixture is formulated as an uncoated tablet to be chewed and taken as 2 tablets on the average of 4 times per day. It is a dark brown, mottled tablet with the bitter taste of unsweetened licorice.
Several recent reports of studies using DGL indicated that the inclusion of antacids was not a necessary component to heal ulcers in laboratory animals and furthermore, that adequate dispersion of the DGL was necessary (capsules of DGL alone were not as effective clinically). In one study it was described that 7 patients out of 17 discontinued taking the medication because of the bitter taste of chewable tablets. In fact, the necessity of chewing 8 tablets a day is a real deterrent to patients taking the medication. It is a well-known fact that patient compliance drops dramatically with the increase in the number of tablets that have to be consumed. Several components of the current formulation, i.e. bismuth salts and aluminum compounds have recently been shown to have neurotoxic side effects.
Recent studies have demonstrated profound healing effects of DGL alone in rats who have aspirin (ASA), stress or restraint induced ulcers. Furthermore, in spite of recent clinical data demonstrating clinical effects of the current DGL formulation that are comparable to or better than cimetidine and ranitdine Caved-S sales have fallen over 90% in the last 5 years concurrent with the availability of tagamet, a product that is a tasteless tablet to be swallowed 4 times a day. In summary, because of a constellation of drawbacks, including drawbacks 1-4 listed below, the current formulation of DGL, while possessing reasonable clinical activity for treating peptic ulcers, is both a medical and marketing failure.